Metallic article



Lbs. in the series of ternary copper-silicon-zinc alloys, r Electrolytic grade copper 490 i h m n mu with silicon from about l Metallic silicon 18 there 5 t e s a g p 45 25 lbs. each.

Patented Aug. 9, 1938 I I. v

IVIETALLIC ARTICLE Louis S. Deitz, Jr., Wcstfield, N. J., and Hanley H. Weiser, Annadale, N. Y., assignors to Nassau Smelting and Refining Company, Incorporated, New York, N. Y., a corporation New York No Drawing. Application January 7, 1938,

Serial No. 183,833

3 Claims. (01. 75-155) This invention relates to metallic articles made specimens were cut from opposite sides at the from an alloy having an unusually high elongabottom, and, tested to rupture under tensile tion, and more particularly to metallic articles stress, gave elongatlons of 78% and 85% respecof silicon bronze having elongations of upwards tively.

5 of 40% when made by casting in sand. Another portion of the same material cast in 5 There is a myriad of purposes for which metal sand gave specimens showing respective elongaarticles or parts are desired-which shall be tough, tions of 42%, 49.5%, 62.5% and 77.5%. strong and if put under stress too great for their Two other lots of similar alloy were prepared strength shall yield gradually and extensively bewith the following compositions by analysis: fore the final rupture occurs.

10 An object of the present invention is to pro- 3 5 Page! vide a metal alloy and articles or parts made Copper 95 97 96 08 (by difl ence) from such alloy by casting, such that the cast Silicon articles or parts shall be ornamental and gen- Zinc erally non-corroding as to surface as Well as n I l5 tough and strong in material and in which th When chill cast in iron molds and tested these material presents an unusually great capacity gave, re pe t v y, and elonga for elongation before rupture under excessive while, when a in se d. their p t v elongafensile stress. tions were 74.5% and 65%.

With the above and other objects in view, the ys o ppe silicon and Zinc closely pinvention may be embodied in articles made by proximating these in composition are well known. 20 casting, either in chill molds or sand molds, an or e ample a. Well known al oy f cast artialloy consisting of copper with 0.75% to 1.45% cles has approximately zinc and 2.75% to 3.50% silicon, which is found er e t to show elongations of upward of 40% and in Copper 94.75 25 some instances as high as 80% to 85% when cast, Silicon I 4.25 and without any special heat treatment or other Zinc 1.00

conditioning to produce such character.

Other objects and features of the invention will appear from the following description of embodiments thereof in cast articles of silicon bronze. Into a clay-graphite crucible in a coal-coke fired pit iurnace were charged However, this material, containing silicon in excess of 4%, shows elongations of only 12% to 24%, the best being equivalent to only about one 30 half the worst value of the alloys described above.

It appears that within a closely circumscribed and limited range of values of the silicon and zinc 2.75% to about 3.50% and zinc from about 0.75% and enou h ranulat d cha co to mekeabout to about 1.45%, the balance, except for negligible a two inch cover on the melt. The charge was impurities, being copper, which group presents me1ted at F-- n stirred briefiyelongations having values from two to seven or i 40 The crucible was lifted out of thefumace, enough eight, times as great a alloys of the same series 0 charcoal skimmed oil to give clear pouring, and and closely similar composition. there w d d /.2 smelter (metallic As noted above, these clongations are shown The zinc having: been stirred in, the charge was by t alloy a ost without any special subse- Dou at about 2 60 F.'into in roughly of quent treatment such as annealing or other heat treatment to develop this character. Hence arti- '45 These in on analy is showed he foll wi clescast from the alloy will have this elongation p s without further treatment.

I Articles cast from the alloy described will be Per cent or particular value when used in circumstances C pp 95-30 where sudden shocks o1 considerable magnitude 50 211110011 may be expected. The articles will then deform instead of rupturing. Thus for example, fittings Some of this material was chill cast in an iron and accessories for plumbing, for communication mold as a .bar about nine inches long, three and tubes and the like in battleships and other ships a half inches wide and three inches deep. Two of war would tend to be much less easily put out of usefulness by exploding shells or other shocks.

It is understood that ternary alloys of 2.75% to 3.50% silicon and 0.75% to 1.45% zinc and the rest substantially all copper fall within a class of alloys which are old and well known in the art. But until the present discovery,'it is believed that the unexpected properties of the specific and narrow range herein disclosed were entirely unknown. nor was the peculiar value of articles and parts intended to be subjected to tensile stress known, when'these articles are simply, cheaply and reliably made by direct casting from these alloys without need for further apparatus or procedures for subsequent treatment. Hence no claim is being made to the alloy as tain only to cast articles made from the specific alloys and having the extraordinary properties described.

such, as the invention is believed to per What is claimed is:

1. Cast metal articles having elongations before rupture under tensile stress of upwards of 40%, and made of an alloy consisting of silicon 2.75% to 3.50%, zinc 0.75% to 1.45%, and the balance substantially all copper.

2. Cast metal articles having elongations before rupture under tensile stress of upwards of 40%, and made of an alloy consisting of silicon 2.95% to 3.35%, zinc 0.95% to 1.25%, and the balance substantially all copper.

3. Cast metal articles having elongations' before rupture under tensile stress of upwards of 40%, and made of an alloy consisting of about 3.35% silicon, about 1.24% zinc, and the balance substantially all copper.

LOUIS S. DEITZ, JR. HANLEY H. WEISER. 

